Magneto-electric generator.



N. M. HOPKINS.

MAGNETO ELECTRIC GENERATOR.

APPLICATION FILED MAY 20, 1913 1,15 ,520. Iatented Aug. 1?, 1915.

- ww 9. 7 4%? WM/Ww W%%%4) 1,150,520.; I Originalapplication filed -Aug'ust 1, 1912, Serial No. 712,738.. Divided and this application filed May 20,

STATES PATENT oFrrcE.

' 1mm ormon HOPKINS, or wasnme'ron, nrs'rnrcr OFCOLUMBIA; nssrenon TO THE ELECTRIC TACHOMETER COMPANY, OF PHILADELPHIA, PENNSYLVANIA, A

cone-cannon or New annsnr.

maei nro-nhncrnrc ennnmron.

. Specification of Letters Patent.

Patented Aug. 17, 1015.

1913. Seria1No.768,85 8.

To all whom it may concern:

Be it known that I, NEVIL Monroe Horrms," a citizen of the United States, residing at Vashington, District of Columbia, have invented certain new and useful Improvements in Magneto-Electric, Generators, of 1 which the. followingis a specification.

This heratorjis especially designed for use in t e tachometerconstituting the subject-matter bf my. Patent No. 1,078,200,

"dated Nov. 11, 1913,' 0f which the present case is a division.

The generator' is constructed to furnish two-phase current,and comprises a permanent magnet having laminae with integral extensi'ons constituting pole-pieces, a winding'on each pole-piece and parallel soft-iron inductors respectively opposed to the polepieces and angularly displaced relatively to each other. The laminae are magnetically united in proximity to the pole-pieces by i side walls of which is-a laminated perma-v.

soft-iron rivets. This construction. provides for the use 0 the full magnetic flux of 'the entire laminated magnet, this full flux threading the two polar windings alternately.

Referring to the accompanying drawmg- Figure 1 is an end elevation of the generator, with the driving-pinion and one endplate \removed; and- Fig. 2 is a plan view of the generator, itscase being shown in section.

. The generator comprises in a preferred embodiment a cylindrical waterand dustproof case 1, 'Wltllill and closely'fittmg the nent' magnet 2 in the form of an interrupted annul s. -The opposite ends of this magnet have large cylindrical passages 3, which receive closely-fitting soft-iron rivets 4 serv-' i'ng magnetically to unite the laminae. The

end "5 of the magnetconstitutes one polepiece, and hasavertical arc-shaped recess 6. The other end 7 of the magnet has two adjacent projecting taper concave-faced polelipieces 8, 9, provided by integral extensions "ofy-the corresponding laminae. Pole-p1ece8 "carries aywinding 10 and pole-piece 9 carries awi'nding 11:- The rotor of this generator consists of two parallel inductors 12, 13, of

"soft iron,'-rigidly mounted with a relative ngular displacementof 459011, a central in .ductor shaft 14, which is journaled at its ends in bushings 15 seated in the end-plates 16, 1'? of the generator casing. This shaft, being of small diameter, only slightly decreases the-magnetic permeability of the inductors. Shaft 14 carries at one end a gear 18, which meshes with a gear 19 fixed on a larger shaft 20 centrally journaled-in and extending through the end-plate 16. Shaft [20 carries an external pinion 21. adapted to engage a driving gear-wheel. \Vhen the inductors 12, 13 are set in rotation, two-phase current,- or two alternating currents out of phase with each other by an angle of 90 electrically, are induced in the windings 1O, 11, each phase winding utilizing substantially the entire flux of .the magnet.

-When one of the two revolving inductors,

as illustrated the inductor 13, is momentarily in position tofully shortcircuit the magnetic flux between the magnet pole-piece 5 and the wound pole-piece 9 the soft-iron rivets 4 transmit the flux from the other circuit is then partially interrupted by the disalinement of inductor 12, to the laminae constituting the pole-piece 9, so that the full power. of the magnet is utilized to satulaminae of the magnet, where the magnetic rate the pole-piece 9 and thereby increase the strength of the currents generated in the winding 11. As the inductors rotate farther, bringing the inductor 12 in alinement with the corresponding gap, the rivets l similarly transmit the flux from the more remote laminae. One or the other of the two inductors 12, 13 at all times acts as a magnetic bridge or armature for all of the assembled laminae, the combined flux of .which is carried by the soft-iron rivets 4,

- laminated permanent magnet, having laminae extended at adjacent points to form parallel pole-pieces integral therewith, windings on said pole-pieces, and inductors respectively opposed to said pole-piecesand angular-l displaced relatively to each uther.

2'. An electric generator, comprising a laminated )ermanent ma net. havin lam-' inaextended at adjacent points to form parallel pole-pieces integral therewith. windings on said pole-pieces. a soft-iron member magneti ally uniting the laminae which comprise said p0lepieces. and inductors respectively opposed to said pole-pieces and angularly displaced relativel to each other.

.3. An electric generator. comprising a laminated permanent magnet. having lam- Copies of this patent may be obtained for five cents each, by addressing the allel pole-pieces integral therewith, wind-- ing's on said pole-pieces, soft-iron rivets magnetically unitingthe-laminae which comprise said pole-pieces, and inductors respectively oppused to said pole-pieces and having an angular displacement of 45 relatively to each other. In testimony whereof I-aflix my signature in presence of two witnesses. XEVIL MONROE HOPKINS. \Yitnesses:

\VALTER O. Bmcnwoon, X. P. LEONARD.

Commissioner of raten'ts.

Washington, D. O." 

